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1.
Sci Rep ; 9(1): 10062, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296894

RESUMO

One of the major consequences of the lack of a functional VHL protein in von Hippel-Lindau disease, a rare cancer, is the constitutive activation of the HIF pathway. This activation ends up in the generation of Central Nervous System (CNS) Hemangioblastomas among other tumours along the lifespan of the patient. Nowadays, only surgery has been proven efficient as therapy since the systemic attempts have failed. Propranolol, a non-specific ß1-and ß2-adrenergic receptor antagonist, was recently designated as the first therapeutic (orphan) drug for VHL disease. Nevertheless, its ß1 affinity provokes the decrease in blood pressure, being not recommended for low or regular blood pressure VHL patients. In order to overcome the ß1-drawback, the properties of a high specific ß2-adrenergic receptor blocker named ICI-118,551 have been studied. ICI-118,551 was able to decrease Hemangioblastomas cell viability in a specific manner, by triggering apoptosis. Moreover, ICI-118,551 also impaired the nuclear internalization of HIF-1α in Hemangioblastomas and hypoxic primary endothelial cells, reducing significantly the activation of HIF-target genes and halting the tumour-related angiogenic processes. In this work, we demonstrate the therapeutical properties of ICI-118,551 in VHL-derived CNS-Hemangioblastoma primary cultures, becoming a promising drug for VHL disease and other HIF-related diseases.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Núcleo Celular/metabolismo , Neoplasias do Sistema Nervoso Central/metabolismo , Hemangioblastoma/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Propanolaminas/farmacologia , Doença de von Hippel-Lindau/metabolismo , Apoptose , Neoplasias do Sistema Nervoso Central/complicações , Hemangioblastoma/complicações , Humanos , Terapia de Alvo Molecular , Mutação/genética , Neovascularização Patológica , Transdução de Sinais , Células Tumorais Cultivadas , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/complicações
2.
Br J Anaesth ; 119(4): 655-663, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121283

RESUMO

BACKGROUND: Recent studies report the immunomodulatory lung-protective role of halogenated anaesthetics during lung resection surgery (LRS) but have not investigated differences in clinical postoperative pulmonary complications (PPCs). The main goal of the present study was to compare the effect of sevoflurane and propofol on the incidence of PPCs in patients undergoing LRS. The second aim was to compare pulmonary and systemic inflammatory responses to LRS. METHODS: Of 180 patients undergoing LRS recruited, data from 174 patients were analysed. Patients were randomized to two groups (propofol or sevoflurane) and were managed otherwise using the same anaesthetic protocol. Bronchoalveolar lavage (BAL) was performed in both lungs before and after one-lung ventilation for analysis of cytokines. Arterial blood was drawn for measurement of the cytokines analysed in the BAL fluid at five time points. Intraoperative haemodynamic and respiratory parameters, PPCs (defined following the ARISCAT study), and mortality during the first month and yr were recorded. RESULTS: More PPCs were detected in the propofol group (28.4% vs 14%, OR 2.44 [95% CI, 1.14-5.26]). First-yr mortality was significantly higher in the propofol group (12.5% vs 2.3%, OR 5.37 [95% CI, 1.23-23.54]). Expression of lung and systemic pro-inflammatory cytokines was greater in the propofol group than in the sevoflurane group. Pulmonary and systemic IL-10 release was less in the propofol group. CONCLUSIONS: Our results suggest that administration of sevoflurane during LRS reduces the frequency of the PPCs recorded in our study and attenuates the pulmonary and systemic inflammatory response. CLINICAL TRIAL REGISTRATION: NCT 02168751; EudraCT 2011-002294-29.


Assuntos
Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/farmacologia , Pneumopatias/epidemiologia , Pulmão/cirurgia , Ventilação Monopulmonar/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido da Lavagem Broncoalveolar , Comorbidade , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/metabolismo , Propofol/farmacologia , Sevoflurano/farmacologia , Síndrome de Resposta Inflamatória Sistêmica/metabolismo , Tempo , Adulto Jovem
3.
Exp Gerontol ; 73: 114-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26581911

RESUMO

Inflammation is related to several pathological processes. The aim of this study was to investigate the protein expression of the different subunits of the nuclear factor Kappa b (NFkBp65, p50, p105, p52, p100) and the protein expressions of IkB beta and alpha in the hearts from a murine model of accelerated aging (SAM model) by Western blot. In addition, the translocation of some isoforms of NFkB from cytosol to nuclei (NFkBp65, p50, p52) and ATP level content was studied. In addition we investigated the effect of the chronic administration of growth hormone (GH) on these age-related parameters. SAMP8 and SAMR1 mice of 2 and 10 months of age were used (n = 30). Animals were divided into five experimental groups: 2 old untreated (SAMP8/SAMR1), 2 young control (SAMP8/SAMR1) and one GH treated-old groups (SAMP8). Age-related changes were found in the studied parameters. We were able to see decreases of ATP level contents and the translocation of the nuclear factor kappa B p50, p52 and p65 from cytosol to nuclei in old SAMP8 mice together with a decrease of IKB proteins. However p100 and p105 did not show differences with aging. No significant changes were recorded in SAMR1 animals. GH treatment showed beneficial effects in old SAMP8 mice inducing an increase in ATP levels and inhibiting the translocation of some NFkB subunits such as p52. Our results supported the relation of NFkB activation with enhanced apoptosis and pro-inflammatory status in old SAMP8 mice and suggested a selective beneficial effect of the GH treatment, which was able to partially reduce the incidence of some deleterious changes in the heart of those mice.


Assuntos
Senilidade Prematura/metabolismo , Hormônio do Crescimento/farmacologia , Quinase I-kappa B/metabolismo , Miocárdio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Senilidade Prematura/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Núcleo Celular/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Hormônio do Crescimento/uso terapêutico , Coração/efeitos dos fármacos , Masculino , Camundongos Endogâmicos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Isoformas de Proteínas/metabolismo , Quinase Induzida por NF-kappaB
4.
Biogerontology ; 14(4): 431-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23852044

RESUMO

It has been suggested that the age-related decrease in the number of neurons in the hippocampus that leads to alterations in brain function, may be associated with an increase in apoptosis due to the reduced secretion of growth hormone (GH) and/or melatonin in old animals. In order to investigate this possibility, male Wistar rats of 22 months of age were divided into three groups. One group remained untreated and acted as the control group. The second was treated with growth hormone (hGH) for 10 weeks (2 mg/kg/d sc) and the third was subjected to melatonin treatment (1 mg/kg/d) in the drinking water for the same time. A group of 2-months-old male rats was used as young controls. All rats were killed by decapitation at more than 24 month of age and dentate gyri of the hippocampi were collected. Aging in the dentate gyrus was associated with an increase in apoptosis promoting markers (Bax, Bad and AIF) and with the reduction of some anti-apoptotic ones (XIAP, NIAP, Mcl-1). Expressions of sirtuin 1 and 2 (SIRT1 and 2) as well as levels of HSP 70 were decreased in the dentate gyrus of old rats. GH treatment was able to reduce the pro/anti-apoptotic ratio to levels observed in young animals and also to increase SIRT2. Melatonin reduced also expression of pro-apoptotic genes and proteins (Bax, Bad and AIF), and increased levels of myeloid cell leukemia-1 proteins and SIRT1. Both treatments were able to reduce apoptosis and to enhance survival markers in this part of the hippocampus.


Assuntos
Envelhecimento/fisiologia , Apoptose/fisiologia , Giro Denteado/metabolismo , Hormônio do Crescimento/fisiologia , Melatonina/fisiologia , Animais , Sequência de Bases , Primers do DNA , Hormônio do Crescimento/metabolismo , Masculino , Melatonina/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
5.
Biogerontology ; 14(4): 383-94, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23666345

RESUMO

Changes in the endocrine system have been suggested to act as signaling factors in the regulation of age-related events. Among the different hormones that have been linked to the aging process, estrogens have been widely investigated. They have been associated with inflammatory and oxidative processes and several investigations have established a relationship between the protective effects of estrogens and the mitochondrial function. Mitochondrial DNA is subjected to continuous oxidative attack by free radicals, and the base excision repair (BER) pathway is the main DNA repair route present in mitochondria. We have investigated the effect of estrogen levels on some of the key enzymes of BER in brain and liver mitochondria. In both tissues, depletion of estrogens led to an increased mitochondrial AP endonuclease (mtAPE1) activity, while restoration of estrogen levels by exogenous supplementation resulted in restitution of control APE1 activity only in liver. Moreover, in hepatic mitochondria, changes in estrogen levels affected the processing of oxidative lesions but not deaminations. Our results suggest that changes in mtAPE1 activity are related to specific translocation of the enzyme from the cytosol into the mitochondria probably due to oxidative stress changes as a consequence of changes in estrogen levels.


Assuntos
Encéfalo/fisiologia , Reparo do DNA/fisiologia , Estrogênios/fisiologia , Mitocôndrias Hepáticas/fisiologia , Mitocôndrias/fisiologia , Animais , Feminino , Ratos , Ratos Wistar
6.
J Physiol Biochem ; 68(2): 255-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22167661

RESUMO

Aging is associated to oxidative damage and alterations in inflammatory and apoptotic pathways. Aging impairs secretion of several hormones, including melatonin and estrogens. However, the mechanisms involved in aging of smooth muscle are poorly known. We have studied the changes induced by aging in the colonic smooth muscle layer of female rats and the protective effect of hormonal therapy. We used young, aged, and ovariectomized aged female rats. Two groups of ovariectomized rats (22 months old) were treated either with melatonin or with estrogen for 10 weeks before sacrifice. Aging induced oxidative imbalance, evidenced by H(2)O(2) accumulation, lipid peroxidation, and decreased catalase activity. The oxidative damage was enhanced by ovariectomy. In addition, aged colonic muscle showed enhanced expression of the pro-inflammatory enzyme cyclooxygenase 2. Expression of the activated forms of caspases 3 and 9 was also enhanced in aged colon. Melatonin and estrogen treatment prevented the oxidative damage and the activation of caspases. In conclusion, aging of colonic smooth muscle induces oxidative imbalance and activation of apoptotic and pro-inflammatory pathways. Hormonal therapy has beneficial effects on the oxidative and apoptotic changes associated to aging in this model.


Assuntos
Envelhecimento/efeitos dos fármacos , Colo/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Melatonina/uso terapêutico , Músculo Liso/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Catalase/metabolismo , Colo/crescimento & desenvolvimento , Colo/metabolismo , Ciclo-Oxigenase 2/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacologia , Estradiol/uso terapêutico , Estrogênios Conjugados (USP)/farmacologia , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Melatonina/farmacologia , Músculo Liso/crescimento & desenvolvimento , Músculo Liso/metabolismo , Ovariectomia , Ratos , Ratos Wistar
7.
Biogerontology ; 11(2): 229-43, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19633997

RESUMO

There is now a large body of evidence suggesting that the decline in ovarian function with menopause is associated with spontaneous increases in pro-inflammatory cytokines. On the other hand, oxidative stress has been implicated in the pathogenesis of several alterations due to menopause, and can arise through the increased production of lipid peroxides (LPO) and/or a deficiency of antioxidant defense. The aim of the present study was to investigate the effect of aging and ovariectomy on various physiological parameters related to inflammation and oxidative stress in livers obtained from old female rats and the influence of chronic exogenous administration of estrogens, phytoestrogens and growth hormone on these. Thirty-six female Wistar rats of 22 months of age were used in the present study. Twelve of them remained intact, and the other 24 had been ovariectomized at 12 months of age. Intact animals were divided into two groups and treated for 10 weeks with GH or saline, and ovariectomized animals were divided into four groups and treated for the same time with GH, estrogens, phytoestrogens or saline. A group of 2 month old intact female rats was used as young control. Protein expression of iNOS, HO-1, IL-6, TNFalpha, and IL-1beta were determined by Western blot analysis. The levels of NO( x ), LPO, TNFalpha, IL-1beta, IL-6 and IL-10 were determined in different fractions of the liver. Levels of LPO in the liver homogenates as well as iNOS protein expression and NO( x ) levels were increased in old rats as compared to young animals; this effect was more evident in ovariectomized animals. Pro-inflammatory cytokines TNF-alpha, IL-1beta and IL-6 were significantly increased and anti-inflammatory IL-10 decreased during ageing and after ovariectomy. Aging also significantly increased expression of HO-1 protein and ovariectomized rats showed an additional increase. Hormonal administration to the ovariectomized groups decreased NO( x ), LPO levels and pro-inflammatory cytokines as compared with untreated rats. Significant rise in IL-10 and reductions in the iNOS, IL-6, TNFalpha and IL-1beta proteins expression were also found. Oxidative stress and inflammation induced during aging in the liver are more marked in castrated than in intact old females. Administration of the different hormonal replacement therapies was able to inhibit the induction of pro-inflammatory cytokines and iNOS, decreased the levels of oxidative stress markers and had therapeutic potential in the prevention of liver injury.


Assuntos
Envelhecimento/metabolismo , Citocinas/metabolismo , Estrogênios/farmacologia , Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Ovariectomia , Animais , Feminino , Hormônio do Crescimento/farmacologia , Heme Oxigenase-1/metabolismo , Peróxidos Lipídicos/metabolismo , Modelos Animais , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoestrógenos/farmacologia , Ratos , Ratos Wistar
8.
Biogerontology ; 11(3): 275-86, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19731067

RESUMO

The purpose of this study was to investigate the effect of aging on different parameters related to inflammation, oxidative stress and apoptosis in hearts from two types of male mice models: senescence-accelerated mice (SAM-P8) and senescence-accelerated-resistant (SAM-R1), and the influence of chronic administration of Growth Hormone (GH) on old SAM-P8 mice. Forty male mice were used. Animals were divided into five experimental groups: two 10 month old untreated groups (SAM-P8/SAM-R1), two 2 month old young groups (SAM-P8/SAM-R1) and one 10 month old group (SAM-P8) treated with GH for 30 days. The expression of tumor necrosis factor-alpha, interleukin 1, interleukin 10, heme oxygenases 1 and 2, endothelial and inducible nitric oxide synthases, NFkB, Bad, Bax and Bcl-2 were determined by real-time reverse transcription polymerase chain reaction (RT-PCR). Results were submitted to a two way ANOVA statistical evaluation using the Statgraphics program. Inflammation, as well as, oxidative stress and apoptosis markers were increased in the heart of old SAM-P8 males, as compared to young controls and this situation was not observed in the old SAM-R1 mice. Exogenous GH administration reverted the effect of aging in the described parameters of old SAM-P8 mice. Our results suggest that inflammation, apoptosis and oxidative stress could play an important role in the observed cardiovascular alterations related to aging of SAM-P8 mice and that GH may play a potential protective effect on the cardiovascular system of these animals.


Assuntos
Envelhecimento/fisiologia , Hormônio do Crescimento/administração & dosagem , Coração/fisiologia , Envelhecimento/metabolismo , Animais , Sequência de Bases , Citocinas/metabolismo , Primers do DNA , Masculino , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Pineal Res ; 45(4): 394-402, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18573161

RESUMO

The aim of this study was to investigate the effect of aging and ovariectomy on various physiological parameters related to inflammation and oxidative stress in livers obtained from old female rats, and the influence of chronic administration of melatonin on these animals. Twenty-four female Wistar rats of 22 months of age were used. Animals were divided into four experimental groups: two intact groups that were untreated or given melatonin (1 mg/kg/day), and two ovariectomized groups that also untreated and treated with melatonin (1 mg/kg/day). After 10 wk of treatment, rats were sacrificed by decapitation, and livers were collected and homogenized. A group of 2-month-old female rats was used as young controls. Protein expression of inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), IL-6, TNF-alpha and IL-1beta were determined by Western blot analysis. The levels of nitric oxide metabolites (NO(x)), lipid hydroperoxide (LPO), TNF-alpha, IL-1beta, IL-6 and IL-10 were determined. Levels of LPO in the liver homogenates as well as iNOS protein expression and NO(x) levels were increased in old rats as compared with young animals; this effect was more evident in ovariectomized animals. Pro-inflammatory cytokines TNF-alpha, IL-1beta and IL-6 were significantly increased and anti-inflammatory IL-10 decreased during aging and after ovariectomy. Aging also significantly increased the expression of HO-1 protein, and ovariectomized rats showed an additional increase. Administration of melatonin, both to intact and to the ovariectomized animals significantly reduced NO(x), LPO levels and pro-inflammatory cytokines in the liver as compared with untreated rats. Significant rice in IL-10 and reductions in the iNOS, HO-1, IL-6, TNF-alpha and IL-1beta protein expression were also found in rats treated with melatonin. Oxidative stress and inflammation induced during aging in the liver are more marked in castrated than in intact females. Administration of melatonin reduces both these situations.


Assuntos
Envelhecimento/metabolismo , Fígado/efeitos dos fármacos , Melatonina/farmacologia , Ovariectomia/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Animais , Western Blotting , Feminino , Heme Oxigenase-1/metabolismo , Inflamação/tratamento farmacológico , Interleucinas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
10.
Biogerontology ; 8(5): 469-82, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17476580

RESUMO

The aging theory postulates that this process may be due to the accumulation of oxidative damage in cells and molecules. The present study has investigated the effect of castration in old female rats on various parameters related to the antioxidant properties of several cellular fractions obtained from the liver, and the influence of several chronic treatments on it, both in intact and castrated animals. Sixty-one 22-month-old Wistar female rats, were used. About 21 intact animals were divided into three groups and treated for 10 weeks with GH, melatonin or saline, and 40 ovariectomized (at 12 months of age) animals were divided into five groups and treated for the same time with GH, melatonin, estrogens (Eos), phytoestrogens (Phyt) or saline. All animals were sacrificed at 24 months of age by decapitation. The activity of glutathione peroxidase (GPx) in cytosolic fraction, glutathione-S-transferase (GST) in cytosol and microsomal fractions, and the levels of nitric oxide (NO) and cytochrome C in mitochondrial and cytosol fractions of liver were determined. A decrease in GST activity was detected in cytosol and in the microsomal fraction in ovariectomized animals as compared to intact rats. The activity of GPx was also decreased in ovariectomized as compared with the intact group. NO level was increased and cytochrome C decreased in the mitochondrial fraction of the liver in ovariectomized females as compared with the intact group, respectively. No significant changes after melatonin or GH treatments were found in GPx, GST activity and NO level in mitochondrial fraction in the intact group. Administration of GH, melatonin, Eos and Phyt in the ovariectomized groups significantly increased the GPx, and GST activity in the cytosol and microsomal fraction and decreased the level of NO in the mitochondrial fraction as compared with the untreated rats. A significant increase in the level of cytochrome C in the mitochondrial fraction and a decrease in the cytosol fraction were also found with all treatments. The administration of GH, melatonin, Eos and Phyt to castrated females seem to reduce oxidative changes in the liver from old ovariectomized rats.


Assuntos
Envelhecimento/metabolismo , Estrogênios/farmacologia , Hormônio do Crescimento/farmacologia , Fígado/metabolismo , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fitoestrógenos/farmacologia , Animais , Antioxidantes/metabolismo , Citocromos c/metabolismo , Citosol/metabolismo , Relação Dose-Resposta a Droga , Feminino , Glutationa Transferase/metabolismo , Fígado/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Óxido Nítrico/metabolismo , Ovariectomia , Ratos , Ratos Wistar
11.
Phytomedicine ; 13(7): 468-76, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16785039

RESUMO

Aging seems to be due to the accumulation of oxidative damage in cells and molecules. On the other hand, menopause and ovariectomy induce deleterious effects on different organs and systems that have been shown to be counteracted by estrogens and in a not so evident form also with phytoestrogens. The present study has investigated whether the administration of a commercial soy extract that contains approximately 10% isoflavones was able to modify some parameters related to oxidative stress and inflammation in hepatocytes isolated from old ovariectomized female Wistar rats. Eighteen 22-month-old animals that had been previously ovariectomized at 12 months of age were divided into four groups: ovariectomized control rats, estradiol-treated ovariectomized females and ovariectomized rats treated with isoflavones. Six intact female rats of 2 months of age were used as reference group. Hepatocytes were isolated and cultured, and carbon monoxide (CO) and nitric oxide (NO) release, as well as adenosyl triphosphate (ATP), cyclic guanosyl monophosphate (cGMP), phosphatidylcholine (PC) and lipid peroxide (LPO) content of cells were evaluated. Uterus was also removed and weighed. Hepatocytes isolated from old ovariectomized rats showed a decrease in ATP content as compared to young animals. Age also induced an increase in LPO cell content. NO, CO and cGMP were augmented with age, and PC synthesis showed a dramatic reduction. Treatment with either estradiol or isoflavones were able to improve all the mentioned parameters altered in hepatocytes isolated from old ovariectomized rats, and the magnitude of the improvement was similar for both treatments. Ovariectomy induced a significant reduction in uterine weight, which was significantly counteracted by estradiol treatment but not by isoflavone administration. In conclusion, the administration of a soy extract containing isoflavones seems to prevent oxidative changes in hepatocytes isolated from old ovariectomized female rats, without modifying uterus weight.


Assuntos
Envelhecimento/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Isoflavonas/farmacologia , Menopausa/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Células Cultivadas , Estradiol/farmacologia , Feminino , Menopausa/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Wistar
12.
J Biotechnol ; 118(4): 339-52, 2005 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-16026883

RESUMO

The cloning and sequencing of the rbpa gene coding for a versatile peroxidase from a novel Bjerkandera strain is hereby reported. The 1777 bp isolated fragment contained a 1698 bp peroxidase-encoding gene, interrupted by 11 introns. The 367 amino acid-deduced sequence includes a 27 amino acid-signal peptide. The molecular model, built via homology modelling with crystal structures of four fungal peroxidases, highlighted the amino acid residues putatively involved in manganese binding and aromatic substrate oxidation. The potential heme pocket residues (R44, F47, H48, E79, N85, H177, F194 and D239) include both distal and proximal histidines (H48 and H177). RBP possesses potential calcium-binding residues (D49, G67, D69, S71, S178, D195, T197, I200 and D202) and eight cysteine residues (C3, C15, C16, C35, C121, C250, C286, C316). In addition, RBP includes residues involved in substrate oxidation: three acidic residues (E37, E41 and D183)--putatively involved in manganese binding and H83 and W172--potentially involved in oxidation of aromatic substrates. Characterisation of nucleotide and amino acid sequences include RBP in versatile peroxidase group sharing catalytic properties of both LiP and MnP. In addition, the RBP enzyme appears to be closely related with the ligninolytic peroxidases from the Trametes versicolor strain.


Assuntos
Basidiomycota/enzimologia , Proteínas Fúngicas/genética , Peroxidase/genética , Sequência de Bases , Basidiomycota/genética , Clonagem Molecular , Proteínas Fúngicas/química , Dados de Sequência Molecular , Peroxidase/química , Filogenia , Estrutura Terciária de Proteína
13.
Am J Respir Crit Care Med ; 163(4): 840-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11282754

RESUMO

To determine the influence of glucagon-like peptides on the secretion of human pulmonary surfactant, we used human type II pneumocytes. In these cells, GLP-1(7-36) amide and exendin-4 stimulated phosphatidylcholine secretion (PC) and cAMP formation in a concentration-dependent manner; these effects were reversed by exendin(9-39). No changes were observed with other related peptides. The mechanism by which GLP-1(7-36) amide exerts its stimulatory effect was investigated with various agents that are well known to be stimulators or inhibitors of PC secretion. Thus, 8-bromo-cAMP increased and both Rp-cAMPS and H-89, the latter an inhibitor of protein kinase A (PKA), reduced pulmonary surfactant secretion in type II pneumocytes. Also, GLP-1(7-36) amide and TPA exerted additive effects in stimulating PC secretion, and Calph C, a potent inhibitor of protein kinase C (PKC), blocked most of the effect of GLP-1(7-36) amide. By contrast, both the calcium ionophore A23187 and GLP-1(7-36) amide had additive effects in increasing PC secretion, and the specific inhibitor of Ca(2+)-calmodulin-dependent protein kinase (Ca-CM-PK), KN-62, inhibited the effect of A23187 but did not alter the stimulatory action of GLP-1(7-36) amide. Our findings suggest that both PKA and PKC are involved in the stimulatory effects of GLP-1(7-36) amide on PC secretion, whereas this peptide has no effect on PC secretion through a Ca-CM-PK mechanism.


Assuntos
Pulmão/metabolismo , Fragmentos de Peptídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Adulto , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Glucagon , Peptídeo 1 Semelhante ao Glucagon , Peptídeos Semelhantes ao Glucagon , Humanos , Pulmão/citologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/farmacologia , Fosfatidilcolinas/análise , Surfactantes Pulmonares/efeitos dos fármacos , Valores de Referência , Sensibilidade e Especificidade
14.
Dig Dis Sci ; 45(9): 1865-71, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11052333

RESUMO

Corticosterone, T3, T4, and prolactin serum concentrations at 24 hr (N = 10), 15 days (N = 10), and 45 days (N = 10) of postoperative (postop) evolution were assayed to study the neuroendocrine response to portal hypertension. A triple stenosing ligature of the portal vein was used as the surgical technique of portal hypertension. This technique does not produce mortality and causes a decrease in the serum concentrations of T3 (0.043 +/- 0.009 vs 0.55 +/- 0.08 ng/ml) and T4 (3.93 +/- 0.55 vs 4.65 +/- 0.67 microg/ml) and an increase in those of prolactin (28.61 +/- 20.20 vs 12.84 +/- 3.96 ng/ml) and corticosterone (397.50 +/- 64.17 vs 311.53 +/- 57.41 ng/ml) at 45 days postop. The T3, T4, prolactin, and corticosterone alterations are associated with a persistent increase of TNF-alpha and NO, whose serum concentrations at 45 days postop are, respectively, 1838.33 +/- 247.07 vs 48.89 +/- 8.75 pg/ml and 0.43 +/- 0.13 vs 0.19 +/- 0.01 mmol/ml. TNF-alpha and NO could mediate these hormonal alterations in the evolution of short-term portal hypertension in the rat; thus they are involved in the systemic neuroendocrine response that is induced by this injury.


Assuntos
Corticosterona/sangue , Hipertensão Portal/sangue , Prolactina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Animais , Masculino , Óxido Nítrico/sangue , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/análise
15.
Shock ; 14(3): 300-6, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11028547

RESUMO

Surfactant protein A (SP-A) is thought to play a role in the modulation of lung inflammation during acute respiratory distress syndrome (ARDS). However, SP-A has been reported both to stimulate and to inhibit the proinflammatory activity of pulmonary macrophages (Mphi). Because of the interspecies differences and heterogeneity of Mphi subpopulations used may have influenced previous controversial results, in this study, we investigated the effect of human SP-A on the production of cytokines and other inflammatory mediators by two well-defined subpopulations of human pulmonary Mphi. Surfactant and both alveolar (aMphi) and interstitial (iMphi) macrophages were obtained from multiple organ donor lungs by bronchoalveolar lavage and enzymatic digestion. Donors with either recent history of tobacco smoking, more than 72 h on mechanical ventilation, or any radiological pulmonary infiltrate were discarded. SP-A was purified from isolated surfactant using sequential butanol and octyl glucoside extractions. After 24-h preculture, purified Mphi were cultured for 24 h in the presence or absence of LPS (10 microg/mL), SP-A (50 microg/mL), and combinations. Nitric oxide and carbon monoxide (CO) generation (pmol/microg protein), cell cGMP content (pmol/microg protein), and tumor necrosis factor alpha (TNFalpha), interleukin (IL)-1, and IL-6 release to the medium (pg/microg protein) were determined. SP-A inhibited the lipopolysaccharide (LPS)-induced TNFalpha response of both interstitial and alveolar human Mphi, as well as the IL-1 response in iMphi. The SP-A effect on TNFalpha production could be mediated by a suppression in the LPS-induced increase in intracellular cGMP. In iMphi but not in aMphi, SP-A also inhibited the LPS-induced IL-1 secretion and CO generation. These data lend further credit to a physiological function of SP-A in regulating alveolar host defense and inflammation by suggesting a fundamental role of this apoprotein in limiting excessive proinflammatory cytokine release in pulmonary Mphi during ARDS.


Assuntos
Citocinas/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Proteolipídeos/farmacologia , Surfactantes Pulmonares/farmacologia , Adulto , Líquido da Lavagem Broncoalveolar/citologia , Monóxido de Carbono/metabolismo , Células Cultivadas , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , GMP Cíclico/farmacologia , Citocinas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Proteolipídeos/metabolismo , Proteína A Associada a Surfactante Pulmonar , Proteínas Associadas a Surfactantes Pulmonares , Surfactantes Pulmonares/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
16.
Diabetes Care ; 23(10): 1455-60, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11023136

RESUMO

OBJECTIVE: To evaluate the effectiveness of a nurse-managed smoking cessation intervention in diabetic patients. RESEARCH DESIGN AND METHODS: This randomized controlled clinical trial involved 280 diabetic smokers (age range 17-84 years) who were randomized either into control (n = 133) or intervention (n = 147) groups at 12 primary care centers and 2 hospitals located in Navarre, Spain. The intervention consisted of a 40-min nurse visit that included counseling, education, and contracting information (a negotiated cessation date). The follow-up consisted of telephone calls, letters, and visits. The control group received the usual care for diabetic smokers. Baseline and 6-month follow-up measurements included smoking status (self-reported cessation was verified by urine cotinine concentrations), mean number of cigarettes smoked per day, and stage of change. RESULTS: At the 6-month follow-up, the smoking cessation incidence was 17.0% in the intervention group compared with 2.3% in the usual care group, which was a 14.7% difference (95% CI 8.2-21.3%). Among participants who continued smoking, a significant reduction was evident in the average cigarette consumption at the 6-month follow-up. The mean number of cigarettes per day decreased from 20.0 at baseline to 15.5 at 6 months for the experimental group versus from 19.7 to 18.1 for the control group (P < 0.01). CONCLUSIONS: A structured intervention managed by a single nurse was shown to be effective in changing the smoking behavior of diabetic patients.


Assuntos
Diabetes Mellitus/reabilitação , Educação de Pacientes como Assunto , Abandono do Hábito de Fumar , Fumar , Adolescente , Adulto , Idoso , Aconselhamento , Diabetes Mellitus Tipo 1/enfermagem , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/reabilitação , Diabetes Mellitus Tipo 2/enfermagem , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relações Enfermeiro-Paciente , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/estatística & dados numéricos , Espanha , Resultado do Tratamento , População Urbana
17.
An Sist Sanit Navar ; 22(2): 233-40, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-12886350

RESUMO

This work describes and analyses the prevalence of smoking amongst medical students, their awareness of the methods of smoking cessation and the effectiveness they attribute to these methods and to medical advice. A questionnaire was distributed to students of medicine at the University of Navarra with open questions on the methods of smoking cessation of which they were aware, the effectiveness attributed to each of these and the effectiveness attributed to medical advice. Information was also gathered on: sex, year of study, smoking habit, average number of cigarettes smoked per day and the length of exposure to tobacco. Of 480 valid interviews, the prevalence of active smokers was 27.5% (CI 95%: 23.5-31.9); 4.2% ex-smokers and 68.3% who had never smoked. 42.7% named nicotine patches as a method of cessation and 25.2% nicotine chewing gum. With respect to the effectiveness attributed to each method, a median and interquartile range (IQR) of 20% (0-50) for the nicotine patches, 10% (0-40) for nicotine chewing gum and 20% (1-50) for medical advice. The more senior students and those that had been smoking for longer mentioned nicotine patches more frequently; more women than men knew about nicotine chewing gum. The senior students attributed greater effectiveness to nicotine patches. A future reduction is predicted in the number of active smokers in the medical sector. Amongst medical students the effectiveness of medical advice is overestimated. It is necessary to increase awareness of the methods for smoking cessation amongst medical students.

18.
Arch Surg ; 132(12): 1352-60; discussion 1360-1, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9403543

RESUMO

BACKGROUND: An increase in cyclic guanosine 3',5'-monophosphate (cGMP) due to nitric oxide generation is known to participate in the mediation of the tumor necrosis factor alpha (TNF-alpha) effect in type II cells. Because guanylyl cyclase can be activated also by carbon monoxide (CO), in this study we examined the ability of human type II pneumocytes to produce CO in the presence of cytokines and the relative contribution of this molecule to the TNF-alpha and interleukin 1 effects. DESIGN: Type II pneumocytes were isolated from cadaveric multiple-organ donors by enzymatic digestion, adherence separation of macrophages, and gradient purification. After preculture for 24 hours, cells were cultured for 24 hours in the presence or absence of TNF-alpha, interleukin 1, sodium nitroprusside, N(omega)-nitro-1-arginine, CO, hemin, zinc-protoporphyrin type IX, deferoxamine mesylate, S-adenosyl-L-methionine, alpha-tocopherol, methylene blue (a guanylyl cyclase inhibitor), 8-bromine-cGMP, and combinations of these reagents. Both CO (picomole per microgram of protein) and nitric oxide release to the medium and the cGMP (picomole per microgram of protein) content of the cells were measured. In a different set of experiments, D-glucose labeled with radioactive carbon (14C) was added to the medium, and the labeling of several lipid fractions was determined (picomole per microgram of protein). RESULTS: D-[14C]glucose incorporation into phosphatidylcholine, the main surfactant component, was selectively inhibited in the presence of cytokines, CO, sodium nitroprusside, or 8-bromine-cGMP. The inhibitory effect of TNF-alpha was partially reversed by N(omega)-nitro-L-arginine, deferoxamine, or alpha-tocopherol and totally reversed by methylene blue. Tumor necrosis factor alpha induced an increase in cGMP cell content and in the CO and nitric oxide release to the medium. Hemin increased CO and cGMP production and decreased phosphatidylcholine synthesis. Zinc-protoporphyrin type IX, an inhibitor of heme oxygenase, and all 3 antioxidants, which inhibited CO production, also antagonized the TNF-alpha effect on cGMP and phosphatidylcholine synthesis. CONCLUSIONS: Intracellular cGMP increase due to an endogenous generation of both CO and nitric oxide mediates the cytokine-induced inhibition of surfactant synthesis by type II pneumocytes. Both lipid peroxidation and heme oxygenase activity are sources for the observed CO production.


Assuntos
Monóxido de Carbono/farmacologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Surfactantes Pulmonares/biossíntese , Adolescente , Adulto , Cadáver , Células Cultivadas , Heme Oxigenase (Desciclizante) , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/metabolismo
19.
Eur J Surg ; 163(8): 619-25, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9298915

RESUMO

OBJECTIVE: To investigate the effect of giving lipopolysaccharide (LPS) on lipid peroxidation, and myeloperoxidase (MPO), nitric oxide (NO) synthase, and phospholipase A2 (PLA2) activities in rat diaphragm, and see whether they could be modified by giving pentoxifylline (PTXF) or somatostatin. DESIGN: Randomised experimental study. SETTING: Teaching hospital, Spain. MATERIAL: 76 Wistar rats divided into 4 groups of 19: control (saline/saline), LPS/saline, LPS/PTXF and LPS/somatostatin. INTERVENTIONS: The LPS was given intraperitoneally either 30 minutes (early, n = 10 in each group) or 120 minutes (late, n = 9 in each group) before treatment with saline, PTXF (45 mg/kg) or somatostatin (200 microg/kg) given intraperitoneally. Rats were killed 120 minutes after treatment. MAIN OUTCOME MEASURES: Malondialdehyde (MDA) and conjugated dienes content, and MPO, NO synthase, and PLA2 activities in diaphragmatic tissue. RESULTS: Conjugated dienes and MDA content, as well as MPO, NO synthase, and PLA2 activities were significantly increased in the rats given LPS. Independently of the timing of treatment, both PTXF and somatostatin completely prevented these increases. CONCLUSION: It is possible that treatment with PTXF or somatostatin may reduce the risk of ventilatory failure and speed recovery in septic patients.


Assuntos
Diafragma/efeitos dos fármacos , Lipopolissacarídeos/administração & dosagem , Óxido Nítrico/biossíntese , Pentoxifilina/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Sepse/tratamento farmacológico , Somatostatina/administração & dosagem , Análise de Variância , Animais , Biomarcadores/análise , Intervalos de Confiança , Diafragma/metabolismo , Modelos Animais de Doenças , Masculino , Malondialdeído/análise , Óxido Nítrico/análise , Peroxidase/análise , Distribuição Aleatória , Ratos , Ratos Wistar , Valores de Referência , Sepse/metabolismo
20.
Rev Med Univ Navarra ; 41(3): 167-72, 1997.
Artigo em Espanhol | MEDLINE | ID: mdl-10420922

RESUMO

To identify smoking dependence predictors, 150 active smokers were interviewed. To assess tobacco dependence Fagerström's test was used. The potential associations between smoking dependence and some variables related to life style were investigated. In a case-control study design an induction period > or = 2 months was assumed. After estimating crude odds ratios, a logistic regression model was fitted. The dependent variable was dependence to tobacco smoking. In the multivariate analysis independent predictors, in addition to age, were: a) an earlier hour for starting smoking (OR: 6.08; 95% CI: 2.29-16.2), b) thinking that smoking avoids getting fat (OR: 4.36; 95% CI: 1.50-12.7) and c) not knowing any person with smoking-related pathology (OR: 3.75; 95% CI: 1.36-10.3). Exercise appeared to protect against smoking addiction (OR: 0.36; 95% CI: 0.13-0.98). The knowledge of these factors could help to avoid the development of smoking addiction.


Assuntos
Fumar/epidemiologia , Adolescente , Adulto , Cultura , Exercício Físico , Feminino , Hábitos , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Personalidade , Fumar/psicologia , Espanha , Esportes , Inquéritos e Questionários , Redução de Peso
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